The invention relates to a device for the patient-specific, individual anatomic placement of bore canals when attaching artificial ligaments on bones, in particular for use when placing bore canals on the thigh and lower leg during anterior cruciate ligament reconstruction. Furthermore, the invention relates to a method for the manufacture of a corresponding device.
The invention basically relates to a customized instrument for the patient-specific, individual anatomic placement of bore canals on human or animal bones to attach artificial ligaments. To make the explanation of the teaching according to the invention easier to understand, the cruciate ligament reconstruction is exemplified below, namely in representation of any patient-specific, individual anatomic placement of bore canals for ligament reconstruction.
Holes are drilled on the thigh and lower leg during cruciate ligament reconstruction, for the secure anchorage of artificial cruciate ligaments. The anatomical positioning of the bore canals on the thigh and lower leg (femur and tibia) during anterior cruciate ligament reconstruction is of vital importance for the proper biomechanical post-operative function of the knee. For lack of a sufficiently sound cruciate ligament targeting instrument, malpositioning, specifically malpositioning in excess of more than one centimeter, of the bore canal or bore canals during the surgery is not uncommon. Said malpositioning either results in permanent mobility impairments of the patient, usually associated with pain. In addition, said malpositioning is frequently the reason for “wearing out” of the cruciate ligament reconstruction. This is associated with the risk of instability of the reconstruction and inevitable failure after some time. Complex and expensive revision surgeries are often required, with their outcome always being worse than the one of a properly performed initial surgery with the accurate placement of the bore canals.
The sound knowledge of the anatomy of the joints, in particular the anatomy of the attachment point of the cruciate ligament on the thigh and lower leg as well as the knowledge of different osseous reference points on the thigh and lower leg are the prerequisite for the correct placement of the bore canals. Only then can the commercially available bore canal targeting devices known from the practice, which are usually equipped with a punctiform sharpened targeting arm, be placed in anatomically accurate fashion. The disadvantage of all targeting devices known from the practice is that not only do they require the anatomical know-how and an accurate placement of the targeting device, but they do in fact have a uniform shape, such that the optimal placement of the bore canals is already impossible insofar—for lack of an individual shape of the targeting device. Consequently, errors are inevitable, in particular based on the fact that the majority of cruciate ligament reconstruction surgeries are performed by surgeons who are only treating a small number of torn cruciate ligaments each year.